Biomedical subjects

D Logeart-Avramoglou

Publications and source records attributed to D Logeart-Avramoglou.

3 recordsLinked to original sources

PubMed2005

[Use of growth factors in the repair of bone].

Osteoformation is induced by numerous growth factors that play an important role in bone repair such as fracture healing. They may serve as therapeutic agent in the treatment of squeletal injuries in the orthopeadic and maxillo-facial fields. Among these proteins, Bone Morphogenetic Proteins (BMP) are the only known osteoinductive growth factors. Unfortunately, they are highly susceptible to proteolysis in vivo and require a suitable delivery system to potentiate their biological activity in a local, controlled and durable manner. In this aim, three options are under investigations: (i) osteoinductive materials made of appropriate carrier to release the protein in situ, (ii) in vivo gene therapy in which the gene is directly transfected in cells of the patient or (iii) ex vivo gene therapy in which cells are harvested from the patient, transfected with DNA in culture and then implanted in the defect. These different kinds of BMP delivery will be discussed.

Bone Diseases↗

PubMed1999

Carboxymethyl benzylamide sulfonate dextrans (CMDBS), a family of biospecific polymers endowed with numerous biological properties: a review.

The functionalized dextrans termed carboxymethyl benzylamide sulfonate dextran (CMDBS) represent a family encompassing a wide range of polymers. These soluble macromolecular compounds, which are substituted with specific chemical functional groups, are designed to interact with living systems. By analogy with glycosaminoglycan heparin, a natural highly charged anionic polysaccharide that exerts a variety of biological effects, we postulated that CMDBS compounds also possess binding sites capable of specific interactions with biological constituents, depending on the overall composition of the polymer. The synthesis and heparin-like properties of these CMDBS have been extensively investigated. Thus, it appears that dextran derivatives can mimic the action of heparin in regard to its interactions with antithrombin and serine proteases involved in blood coagulation. Other derivatives interact with various components of the immune system or with adhesive proteins such as fibronectin in modulating the proliferation of Staphylococcus aureus. Because they are able to stimulate wound healing in various in vivo models, these polysaccharides may also constitute a family of tissue repair agents because of their protecting and potentiating effects with heparin binding growth factors. Moreover, dextran derivatives in contact with cells such as endothelial cells, smooth muscle cells, or tumoral cells can affect both cell proliferation and metabolism. It appears that these bioactive polymers are also efficient tools to investigate the precise mechanism of action of individual biological activities by contrasting their mode of action to that of heparin. In addition to their numerous biological properties and biospecificity, functionalized dextrans are relatively simple to manufacture and exempt of donor contaminant, which make them attractive in a variety of clinical applications.

Animals↗

PubMedDate not supplied

Engineering bone: challenges and obstacles.

Repair of large bone defects is still a challenge for the orthopaedic, reconstructive and maxillo-facial surgeon. Availability of pluripotent stem cells from either autologous or allogenic sources and the potential of inducing the osteogenic phenotype is motivating exploration and development of custom-tailored materials known as "bioengineered bone constructs". In such cases, the clinical scenario involves either expansion of stem cells in monolayer and loading them into a porous scaffold prior to surgery or direct cell expansion within the scaffold, and implanting this novel construct back into the donor patient. In this review, we delineate, from an engineering perspective, the progress that has been made to date and the challenges remaining in successfully translating this promising (but not yet definitively established) approach from bench to the bed site.

Animals↗